Developing WordPress sites on a local MAMP server provides flexibility, privacy, and security throughout the development process. Setting up a WordPress environment on MAMP is definitely worth the effort, especially if you’re building and testing multiple sites using WordPress’ built-in MultiSite functionality.

The easiest and recommended way of setting up WordPress MultiSite is to use sub-directories. So when you create a new site named “business”, it will be located at http://localhost/business/. Here’s a mini-tutorial on how to use sub-domains for your network sites.

Edit Mac hosts file

After installing MAMP, change the default Apache port to 80. Next, add your sub-domains to the Mac hosts file. To do this, open Terminal and type “sudo pico /etc/hosts” (without the quotes), and then enter your password at the prompt. Use the arrow keys to scroll down to the end of the hosts file and add the following lines:

Edit these entries to match the domain and sub-domains that you want to create with MultiSite. Add as many sub-domains as needed, now or later. Then save the file and exit by typing Ctrl+O, Enter, and then Ctrl+X.

Edit Apache config file

The next step is to add virtual hosts to your Apache configuration file. Open /Applications/MAMP/conf/apache/httpd.conf in a text editor and scroll down to the line that says “#NameVirtualHost *”. Replace that line with the following code:

6. You can add as many of the above as you need by changing the DocumentRoot, ServerName, ServerAlias and Directory entries accordingly.

This method is very similar to the previous technique, but enables you to add more site definitions and keeps your config file slightly less cluttered.

Install & configure WordPress

Now to install WordPress by placing the WordPress installation files in your /htdocs/ directory, creating the database via phpMyAdmin (@ http://localhost/MAMP/), and editing wp-config.php with your database credentials. Then complete the install process by accessing http://example.com/wp-admin/install.php in your browser.

Next, enable MultiSite by adding the following line to your wp-config.php file, just above the line that says, “That’s all, stop editing! Happy blogging”:

define('WP_ALLOW_MULTISITE', true);

With that in place, return to the WP Admin and click on Tools > Network. On this page you will now see an option to use sub-domains for your site addresses. Make sure that’s selected, check the other details, and then click the “Install” button to make it happen. Note that you’ll see a warning message that says, “Wildcard DNS may not be configured correctly!” – we can ignore this warning because we know our DNS is correct.

Finally, complete the steps outlined there on the “Enabling the Network” page (i.e., create a blogs.dir folder and add the required code snippets). After that, re-login to the Admin area and go to Network Admin > Sites > Add New to begin adding your sub-domain network sites.

That’s it! You’re now rolling tuff with WordPress subdomains on a local MAMP development server. The sky’s the limit!

Now, all you have to do is run this batch file as administrator and it will swap your host files from the everyday file to the development file. Doing this will allow you to switch back and forth between the local development site and the live site.

BONUS:
By editing the httpd.conf file correctly, you could change the document root of your development site to your DropBox folder.

Out of curiosity, is there a particular reason to use MAMP versus the built-in server capabilities of the Mac? (I had to do a MySQL install and tweak a few PHP settings, but otherwise my default install, both in Snow Leopard and Lion, is perfectly happy running a local server…)

Thanks for the tutorial, as it’ll be immensely helpful for me as I set up a new site using Multisite over the next month or two!

Not really. Ultimately they do the same thing, but MAMP provides some additional options and makes it all easier to change settings from it’s handy little control panel. I’m not sure if there’s anything like that for the built-in Mac files..?

I’m wondering if anybody else finds this not possible – I keep revolving back to the WordPress Codex which states;

You cannot choose Sub-domain Install in the following cases:
WordPress install is in a directory (not in document root).
“WordPress address (URL)” is localhost.
“WordPress address (URL)” is IP address such as 127.0.0.1.

There appears to be a change with the latest versions of MAMP.
Now, look for “#Include /Applications/MAMP/conf/apache/extra/httpd-vhosts.conf” and remove the hash at the beginning of the line. Then edit the file referenced in that line.